Shock and/or vibration damping device for use between a supporting element and a supported element

Abstract

The invention relates to a shock and/or vibration damping device comprising a body adapted to be assembled to a supporting element, a concavity provided in the body in which is introduced a piston whose rod is adapted to be assembled to a supported element, and at least one resiliently deformable supporting membrane arranged in the cavity and interposed between the head of the piston and the cavity bottom wall. This membrane is mounted freely slidable at its periphery within the cavity and comprises in proximity to its periphery a stiffening element at least partially embedded in its mass. The head of the piston is advantageously embedded in the mass of another membrane which may be identical with the supporting membrane, the tops of the two membranes bearing against one another and wherein the shape of the surface of one of the membranes is at least partially conformed to the shape of the confronting surface of the other membrane.

What is claimed is: 
     
       1. A shock and/or vibration damping device for use between a supporting element and a supported element, comprising a body adapted to be assembled to one of said elements including a substantially cylindrical cavity having a cavity side wall and a cavity bottom wall, a piston comprising a piston head situated in said cavity and a piston rod, the rod being adapted to be assembled to the other one of said elements and the head being embedded in the mass of a resiliently deformable piston head membrane, and at least one resiliently deformable supporting membrane arranged in said cavity and interposed between the piston head and the cavity bottom wall confronting it, each membrane having a substantially bell-shaped major portion, the shape of the surface of the piston head membrane is at least partially conformed to the shape of the surface of the said supporting membrane on which it bears; the piston head membrane and the supporting membrane are each provided with a respective peripheral skirt portion which is directed towards the top of the respective membrane with a point of inflection defined by the junction of each said peripheral skirt portion and the bell portion of the respective membrane, the peripheral skirt portion thickness of each of said piston head supporting membranes is smaller than the thickness of the membrane major portion to form a thinner, more flexible lip, said flexible lip of said piston head membrane and said supporting membrane freely and slidingly bearing against the side wall of the cavity of said body, said thinner lip having a reverse concavity with respect to that of the membrane bell-shaped major portion, and a stiffening element is at least partially embedded in the mass of at least one membrane close to said point of inflection defined by the junction of said peripheral skirt portion and the bell portion of said at least one membrane provided with said stiffening element. 
     
     
       2. The device of claim 1, wherein said stiffening element is substantially toric in shape. 
     
     
       3. The device of claim 1, wherein said stiffening element is substantially cylindrical in shape. 
     
     
       4. The device of claim 1, comprising two said supporting resiliently deformable bell-shaped membranes interposed between the piston head and the confronting bottom wall of the cavity, both of said supporting membranes being provided with a skirt portion bearing freely and slidingly against the side wall of said body cavity. 
     
     
       5. The device of claim 4, wherein said two supporting membranes interposed between the piston head and the bottom wall of the cavity bear against one another by their peripheral edge and are assembled together by a common stiffening element. 
     
     
       6. The device of claim 5, wherein the top of one of said two supporting membranes bears on the cavity bottom wall facing the piston head and wherein, the top of the other supporting membrane bears against said piston head membrane. 
     
     
       7. A shock and/or vibration damping device for use between a supporting element and a supported element, comprising a body adapted to be assembled to one of said elements including a substantially cylindrical cavity having a cavity side wall and a cavity bottom wall, a piston comprising a piston head situated in said cavity and a piston rod, the rod being adapted to be assembled to the other one of said elements and the head being embedded in the mass of a resiliently deformable piston head membrane, and at least one resiliently deformable supporting membrane arranged in said cavity and interposed between the piston head and the cavity bottom wall confronting it, each membrane having a substantially bell-shaped major portion, the shape of the surface of the piston head membrane is at least partially conformed to the shape of the surface of the said supporting membrane on which it bears and the piston head and supporting membranes are each provided with a peripheral skirt portion which is directed towards the top of the respective membrane with a point of inflection defined by the junction of said peripheral skirt portions and the respective bell portions of the membrane, the peripheral skirt portion thickness of each said piston head and supporting membranes is smaller than the thickness of the major portion of said respective membranes to form a thinner, more flexible lip on each membrane, said flexible lip of each of said membranes freely and slidingly bearing against the side wall of the cavity of said body, said thinner lip of said piston head membrane having a concavity directed towards the bottom wall of the cavity of said body, a stiffening element is at least partially embedded in the mass of each membrane close to said point of inflection defined by the junction of said peripheral skirt portion and the bell portion of each membrane, each said stiffening element being substantially cylindrical in shape and said skirt portion of each membrane is provided with a cylindrical annular open slot concentric with said body and in which is at least partially accommodated a respective one of said stiffening elements. 
     
     
       8. A shock and/or vibration damping device for use between a supporting element comprising a body adapted to be assembled to one of said elements including a substantially cylindrical cavity having a cavity side wall and a cavity bottom wall, a piston comprising a piston head situated in said cavity and a piston rod, the rod being adapted to be assembled to the other one of said elements and the head being embedded in the mass of a resiliently deformable piston head membrane, and at least one resiliently deformable supporting membrane arranged in said cavity and interposed between the piston head and the cavity bottom wall confronting it, each membrane having a substantially bell-shaped major portion, the shape of the surface of the piston head membrane is at least partially conformed to the shape of the surface of a first supporting membrane on which it bears and the piston head membrane is provided with a peripheral skirt portion which is directed towards the top of the piston head membrane with a point of inflection defined by the junction of said peripheral skirt portion and the bell portion of the membrane, the peripheral skirt portion thickness of said piston head membrane is smaller than the thickness of the major portion thereof to form a thinner, more flexible lip, said flexible lip of said piston head membrane freely and slidingly bearing against the side wall of the cavity of said body, said thinner lip having a concavity directed towards the bottom wall of the cavity of said body; a second supporting membrane provided with a skirt portion, said two supporting membranes bearing against one another by their peripheral edge and assembled together by a common stiffening element, an annular slot is provided in the skirt portion of each supporting membrane, said slots opening opposite one another, and wherein said common stiffening element is constituted by a cylinder of sufficient size to be inserted simultaneously into said slots of said membranes. 
     
     
       9. A shock and/or vibration damping device for use between a supporting element and a supported element, comprising a body adapted to be assembled to one of said elements including a substantially cylindrical cavity having a cavity side wall and a cavity bottom wall, a piston comprising a piston head situated in said cavity and a piston rod, the rod being adapted to be assembled to the other one of said elements and the head being embedded in the mass of a resiliently deformable piston head membrane, and at least one resiliently deformable supporting membrane arranged in said cavity and interposed between the piston head and the cavity bottom wall confronting it, each membrane having a substantially bell-shaped major portion, the shape of the surface of the piston head membrane is at least partially conformed to the shape of the surface of a first supporting membrane on which it bears and the piston head membrane is provided with a peripheral skirt portion which is directed towards the top of the piston head membrane with a point of inflection defined by the junction of said peripheral skirt portion and the bell portion of the membrane, the peripheral skirt portion thickness of said piston head membrane is smaller than the thickness of the major portion thereof to form a thinner, more flexible lip, said flexible lip of said piston head membrane freely and slidingly bearing against the side wall of the cavity of said body, said thinner lip having a concavity directed towards the bottom wall of the cavity of said body, a second supporting membrane being present and interposed between the piston head and the confronting bottom wall of the cavity, both of said supporting membranes being provided with a skirt portion bearing freely and slidingly against the side wall of said body cavity, said two supporting membranes bearing against one another by their peripheral edge and assembled together by a common stiffening element, an annular slot is provided in the skirt portion of each supporting membrane, said common stiffening element including a flat ring arranged between the membranes and provided on both sides with a centering element accommodated in corresponding ones of the slots of the membranes. 
     
     
       10. The device of claim 1, wherein said piston head membrane and said supporting membrane interposed between the piston head and the bottom wall of the cavity of said body are substantially identical, said piston head membrane displaying a concavity directed towards the piston rod. 
     
     
       11. The device of claim 1, wherein each membrane is mounted in a non-pre-stressed state. 
     
     
       12. The device of claim 1, wherein said stiffening element is made of metal and may comprise at least one element similar to those of tire reinforcements.